All three U.S. stock indices ended the day lower, with the Dow Jones being dragged down by Walmart (WMT). Walmart revealed a disappointing earnings report today, reporting that the retailer's net income dropped by 5% in the first quarter. The mega-retailer sites that the harsh winter weather greatly impacted their earnings report. It seems like General Motors (GM) learned from its previous mistake and issued a recall of nearly 3 million cars and trucks, before any deaths occurred.